Oxytocin is a secreted, peptide hormone that is involved in modulating a wide range of central and peripheral physiological responses. Most notably, it has been implicated in social behaviors, including parental behavior, the formation of social bonds, and the management of stressful experiences. Given the increased interest and important role of this peptide in mammalian behavior, physiology and disease, there is a critical need to establish valid and reliable methods to measure oxytocin in peripheral fluids, such as saliva. Previously published studies have reported oxytocin measurements in saliva samples, suggesting a non-invasive modality for sample collection in the behavioral sciences. However, major concerns have been raised regarding the validity of these past salivary oxytocin measurements. Over the past decade, salivary diagnostics have received increasing attention as a growing number of systemic diseases (i.e. cancer, cardiovascular, and metabolic diseases) and physiological conditions have been shown to be accurately reflected by the composition of saliva. For 15 years, Salimetrics has pioneered salivary bioscience by developing and standardizing immunoassay protocols specifically for use in saliva samples. Salimetrics sees a commercial opportunity to develop a sensitive and reliable immunoassay for measuring salivary oxytocin, which would have a wide-range of applications. Because of the roles of oxytocin in social behaviors, recent research has focused on the potential involvement of oxytocin in the pathophysiology of autism spectrum disorder (ASD). ASD is a neurodevelopmental disease manifesting in childhood but extending through to adulthood. Key symptoms include impairments in social and language functioning and the presence of restricted interests and repetitive behavior. Evidence has accumulated to suggest that polymorphisms of multiple oxytocin-related genes are associated with ASD risk and some studies have reported lower levels of oxytocin in the blood of individuals with ASD; these studies suggest that oxytocin levels might serve as a biomarker for ASD. The goals of this Phase I SBIR are 1). To develop a sensitive and reliable immunoassay for salivary oxytocin measurements; 2). To validate oxytocin levels by mass spectrometry; and 3). To use our salivary immunoassay to evaluate oxytocin as a biomarker for ASD (or ASD-related phenotypes). We have a uniquely experienced team that includes specialists in salivary biosciences and antibody/assay design (Salimetrics), technological validation (Scripps) and pediatric autism (UCLA) to support the development of this salivary oxytocin immunoassay and pilot testing in subjects with ASD.